Hi folks, I will be very grateful if anyone can give me the information Im looking for or direct me to that part of the forum where I can get help.
I have an LG washing machine that just keeps on breaking down so I have decided to build a motor control unit using an old laptop. My main problem is I do not know the stator spec and I dont want to roll in the wrong voltages or I will burn out the coils. I will be very grateful if anyone can give me the required spec for this kind of motor. It is a 3 phase motor but what is the maximum voltage before it goes into melt down?? There are a myriad of schematics out there for 3 phase inverters but no output voltage is stated. Geting this motor spinning is the first step to starting this project, a lot of work still to go after. Thanks for your help.

NB Pls observe attached image

 

I had Fisher and Paykel washers that got humidity into the driver board.
repair was to replace the popped power FETs in the 3 phase "H" bridge, and check other parts. Then spray with clear varnish to keep the condensation off it.

You will probably find the motor is running off the mains volts rectified so depending where you are, 110V * 1.414 = about 160VDC or 240V * 1.414 = about 350VDC.
You need a Brushless DC motor driver. The large connector is the delta connected windings and the small one the hall sensors.
They are not trivial to make. It is worth looking into fixing the original, maybe up rating the FETs if that is what is the problem.

 

I had Fisher and Paykel washers that got humidity into the driver board.
repair was to replace the popped power FETs in the 3 phase "H" bridge, and check other parts. Then spray with clear varnish to keep the condensation off it.

You will probably find the motor is running off the mains volts rectified so depending where you are, 110V * 1.414 = about 160VDC or 240V * 1.414 = about 350VDC.
You need a Brushless DC motor driver. The large connector is the delta connected windings and the small one the hall sensors.
They are not trivial to make. It is worth looking into fixing the original, maybe up rating the FETs if that is what is the problem.

Thanks for your response, I have decided to try and build one cos Im not overall happy with the washing machines programming. I dont think I will find a versatile machine on the EU market, most machines here dont rinse properly, something about economizing water and all that mandy pandy stuff. Anyway, back to the topic at hand, the MCU is buried in a chunk of resin so cannot be fixed. There are no FETs, everything is combined into one inverter ic. Pls may I ask what the 1.414 is, my electronics knowledge is only C&G level 2 1990s, thanks.

 

Basically put, when measuring AC voltage, the meters are calibrated to the equivalent DC value the would produce the same heating effect. This is called the RMS or Root Mean Square value.
But as the AC is a sine wave, and there are "gaps" in the current flow, ( zero, rising to max, then down to zero and the same reversed), the peak voltage is actually higher than the rated value. Because of the shape of the sine wave, the peak voltage is 1.414 times the RMS. And capacitors charging from AC via a bridge rectifier will charge to this peak value. So if you run stuff on AC, you need to take into account this higher voltage.
http://practicalphysics.org/explaining-rms-voltage-and-current.html

 

Basically put, when measuring AC voltage, the meters are calibrated to the equivalent DC value the would produce the same heating effect. This is called the RMS or Root Mean Square value.
But as the AC is a sine wave, and there are "gaps" in the current flow, ( zero, rising to max, then down to zero and the same reversed), the peak voltage is actually higher than the rated value. Because of the shape of the sine wave, the peak voltage is 1.414 times the RMS. And capacitors charging from AC via a bridge rectifier will charge to this peak value. So if you run stuff on AC, you need to take into account this higher voltage.
http://practicalphysics.org/explaining-rms-voltage-and-current.html

Wow, thanks for that, I already have a large capacitor ready for the rectified power and Im planning to drive the IGBT's with 240v dc but on my former plans, I assumed that DC would be produced at the motor itself but from your info, it appears it will be AC. If Ac enters the motor coils, I will not get the effects I planned for as some poles must be North while others are South, AC cannot produce this effect. This will require further investigation.

My first and earlier plans was just to generate 240v DC at certain poles at certain times as programmed into the software but then I realized that the motor can handle 360vdc hence I decided to introduce the inverted circuit. .

 

I just noticed I referred to the windings as being Delta connected when they are "Y" connected. But everything else is ok.
Have a look at...
https://www.nxp.com/docs/en/application-note/AN4776.pdf
https://www.nxp.com/docs/en/application-note/AN4058.pdf

https://www.infineon.com/dgdl/ap161...e.pdf?fileId=db3a3043139a1bac0113aacbc6ab02e6

There is a lot of info on line to help you understand how to drive your motor.

 

I just noticed I referred to the windings as being Delta connected when they are "Y" connected. But everything else is ok.
Have a look at...
https://www.nxp.com/docs/en/application-note/AN4776.pdf
https://www.nxp.com/docs/en/application-note/AN4058.pdf

https://www.infineon.com/dgdl/ap1611710_speed_control_bldc_hall셤davedrive.pdf?fileId=db3a3043139a1bac0113aacbc6ab02e6

There is a lot of info on line to help you understand how to drive your motor.

Thanks, my motors winding is a star but I will check the links u sent

 

I have a direct drive motor with the controller which is rectified AC to DC power 110 volt AC on the controller it has a plus five s negative when I put 120vac
to the board the motor basically feels very hard to spend I do not know what to plug into the Plus s negative port please help. This motor is 36 poles also 42 Mag could someone help me with the kilowatt rating of this motor as well

 

This motor is 36 poles also 42 Mag could someone help me with the kilowatt rating of this motor as well

Is this a Fisher-Paykel motor as shown earlier?
If you have the machine it came from, Look at the wattage rating of the machine as the motor is the main source of consumption.
If you ask the motor manuf. for sizing, you may get the same answer as Rolls-Royce offers when you ask for motor HP.
Sufficient!!

 

I have a direct drive motor with the controller which is rectified AC to DC power 110 volt AC on the controller it has a plus five s negative when I put 120vac
to the board the motor basically feels very hard to spend I do not know what to plug into the Plus s negative port please help. This motor is 36 poles also 42 Mag could someone help me with the kilowatt rating of this motor as well

I know what you're talking about i'm sitting here looking at that same circuit board myself right now And I took the motor out of the washing machine long ago The power board it has which is the same one you have pictured there Only has three plugs to it but 110 in The UV and W out to the motor And then just above that it connected that says five volts positive Data and then ground When I put this thing into 110 volts The motor twitches Once or twice as the Condensers Fill up And then becomes lax again Letting me know that the board is in good condition and all so I moved on to the next step which is Testing the three blue wires that go to the Positive 5 volts Ground and data To an electrical voltmeter On the voltage side when I plug it into power no matter which configuration I use on those three wires it says nothing about any kind of power coming out and having played around with it enough USB devices It came to me that This is most likely AUSB input They could be utilized up for computer if you had the programming to tell what to do with itself does anybody up there know such a program Or maybe an adrenal project that would Tell this power board what to do with its motor

 

OK thank you I did not know that\

 

My advice is to just leave the motor alone. Your questions indicate to me a basic lack of electronics knowledge and while I encourage folk to have a play with electronics as it is a fascinating field to get into, this sort of motor can be quite lethal. Start your electronics journey with maybe an Arduino kit, running on 12V, not a high power mains device.
Just because

Then I started thinking data 5 bolts USB It's gotta be input USB

5 Volts data does not necessarily indicate USB at all, and I very much doubt it will be if you are referring to the boars shown earlier.

Please keep safe and star away from mains devices until you develop a bit of experience.

 

Hi,
When our LG washer went kaput, I looked on YouTube and saw plenty of repairs done in India/Pakistan.
I got overruled, and WE purchased another LG. The old one had given us good service.
The motor had stopped operating.
Good luck..............